Crankshaft



April 16, 1940.

NT M. Y'LAwLEss 2,197,413

CRANKSHAFT Filed July 25, 1939 Ijzvezz fof zhazyllaziess Jjy PMQM;

Patented Apr. 16, `194-0 UNITED 4srlxrss- PATENT oFFlcE;

CRANEsirfurr` Nathan M. Lawless, Moline, I-l}.,-assignor to Intern. y inational Harvester Company, a corporation of Application July 25, 1939,Serial No. 286,355

7 Claims.

A further object is to provide a crankshaft ofv a plurality of partsweldedv together.

According to the present invention, cranks and pins are fabricated ofindividual parts, and theyvr are welded together with the pins beingem'- braced by notches in the ends of the cranks.

In the drawing- Figure 1 is a side view of the crankshaft of the presentinvention;

Figure 2 is an end View of the same;

Figure 3 is a View partially in section, showing how the parts of thecrankshaft are welded to-` gether;

Figure 4 is a view taken along the line 4 4 of Figure 3; and,

Figure 5 is a detail View of a crank.

The crankshaft of the present invention comprises a series of short pinsor shafts I connected to one another by a series of cranks Il. Each pinis of circular section so as to form a bearing for some member connectedthereto. In the present instance, the pins are to be connected to strawracks of a thresher, which are not shown. It will be understood, ofcourse, that the crank- 'shaft is adapted for other uses.

As shown in Figures 3 and 5, each crank is in the form of a flat bar,generally rectangular in section and substantially larger in onedimension than in the other, and is provided with a notch I2 in each endto a depth somewhat larger than half its width, which is substantiallyequal to the diameter of the pin vIIJ'. The notch has rounded corners.The wall of the notch is perpendicular to the side faces of the crank.The ring I3 is placed over each end of the pin, and the end of the pinis made to t Within the notch I2 of the crank Il. Then Weld metal isdeposited on the parts so as to weld the ring I3 and the pin l0, as atI4, and the pin H) and crank il, as at l and I6. It will be observed inFigure 3 that, because the crank extends from the pin at an obtuse angleand the notch wall is at substantially right angles to the faces of thecrank, the pin occupies only part of the notch and leaves a pocket forthe weld metal I6. Similarly, pockets are provided, as at I1, adjacentthe points where the crank l l is closest to the ring 30.

As stated above, the depth of each notch l2 is somewhat more than halfits Width, sothat the notch approximates the shape of half of anl `ellipse. In order that the crank Il, extending at lan obtuse angle fromthe'pin I0, may contact all parts of the pin embraced, the notch shouldtheoretically be of elliptical shape. Actually, any shape notch whichwill embrace the pin is satis-v factory, for the weld metal will fill upany space between the pin and the notch. It is obvious thatv the `widthof the crank must be greater than the ciently thick so that the torquestrength is equal y to that of the pin.

It will be apparent from the foregoing description` that a novelcrankshaft has been provided, which is cheap and easy to manufacture andyet possesses the requisite strength. The particularv shape of the partsand the way in which they are assembled provide natural pockets for weldmetal which holds the parts together.

The .intention is to limit the invention only within the terms of theappended claims.

What is claimedis: l.` In combination, a pin, and a crank having a notchin one end embracing an end of the pin and being welded to the pin.

2. In combination, a crank having a notch in one end, a pin partiallyembraced by the notch in the crank and extending obliquely therefrom soas to leave a space in the notch, and weld material positioned in thespace in thenotch and joining the pin and the crank. 3. In combination,a crank having a notch i one end, a pin partially embraced by the notchin the crank and extending obliquely therefrom so as to leave a space inthe notch, a ring surrounding thepin at a point adjacent the notch inthe crank, weld material positioned in the space in the notch andjoining the pin and crank,` and weld material contacting side surfacesof the pin, the ring, and the end portion of the crank and joining thepin to the ring and to the crank.

4. In combination, a pin of round section, a crank of rectangularsection of which one dimension is greater than thepin diameter and theother dimension is-less, saidcrank having a notch in the end embracingthe end ofthe pin, and

weld'metal in the notchjoining the pin and the crank.

5. In combination, a pin of round section, a

15 diameter of the pin. The crank is made suff crank havingapproximately the same torque strength as the pin and being ofrectangular section of which the dimensions are respectively greater andless than the pin diameter, the crank having a notch in the endembracing the end of the pin, the pin extending obliquely` from thecrank and thereby leaving a space in the notch, and Weld metal in thespace of the notch joining the pin and the crank. y v

6. In' combination, a pin of round section, a crank of rectangularsection of which the dimensions are respectively greater and less thanthe pin diameter, the crank having a notch in the end embracing the endof the pin, a ring surrounding the end of the pin adjacent the crank,

and weld metal joining the ring, pin, and crank.

7. In combination, a pin of round section, a crank having approximatelythe same torque strength as the pin and being of rectangular section ofwhich the dimensions are respectively greater and less than the pindiameter, the crank having a notch in the end embracing the end of thepin, the pin extending obliquely from the crank and thereby leaving aspace in the notch, a ring surrounding the end of the pin adjacent thecrank, and Weld metal in the space in the notch joining the crank andpin and also between the pin and ring to join the same.

NATI-IAN M. LAWLESS.

